Prostate-specific antigen and risk of bone metastases in west Africans with prostate cancer

World J Nucl Med. 2019 Apr-Jun;18(2):143-148. doi: 10.4103/wjnm.WJNM_38_18.

Abstract

We aimed to assess the relationship between bone scintigraphy findings and prostate-specific antigen (PSA) and Gleason score in a group of treatment naïve West Africans with prostate cancer. The age, PSA, and Gleason scores of 363 patients with prostate cancer were collected. Patients were risk stratified using the D'Amico criteria. Logistic regression was performed to assess the relationship between bone scan results and PSA and Gleason score. Receiver operating characteristics (ROC) analysis was used to determine the diagnostic reliability of the bone scan findings. Ninety of the 96 patients with metastases had high risk, and only 6 had low-to-intermediate risk disease (P = 0.0001). PSA (odds ratio [OR] 2.4 [95% confidence interval [CI] 1.5-3.8], P = 0.001) and GS (OR 2.2 [95% CI 1.5-3.1], P = 0.001) were independently predictive of the presence of metastases. ROC analysis revealed that PSA predicted the presence of metastases with an area under the curve of 0.72, and using a cut-off value of ≥20 predicted metastases with a sensitivity of 86.5% and specificity of 41.2%. A Gleason score of ≥7 had an 89.6% sensitivity and 34.8% specificity for bone metastases. Using a Gleason cutoff of ≥8, the sensitivity and specificity for predicting bone metastases were 54.2% and 71.5%, respectively. The area under the Gleason score ROC curve was 0.68. PSA and Gleason score are independent predictors of the presence of bone metastases in West Africans with prostate cancer.

Keywords: Bone scintigraphy; Ghana; Gleason score; prostate cancer; prostate-specific antigen.